The present invention relates to a rail mounted safety restraint device, and more particularly to a worker's fall arrest line anchor for releasably securing to a rail of a railway.
One of the most common activities of railway construction and maintenance workers is that of walking on or passing along an exposed walkway such as exists on any given railway bridge. Increasingly fall arrest systems incorporating restraint lines, lanyards or other such tether devices are being required for railway workers. Such lines, lanyards and tethers will normally be secured, at one end, by way of a hook to a worker's belt or harness, and, at the other, to an anchor device. The major difficulty is that there is often no anchorage point to which a suitable fall arrest system can be attached to give protected freedom of work movement and/or allow unhindered safe passage along a railway bridge. Thus, if the worker were to inadvertently fall off of the bridge or overpass, the fall arrest device, tether or lanyard would break the person's fall and reduce or avoid injury or death to that person.
U.S. Pat. No. 4,606,430 issued Aug. 19, 1986 of Roby et al teaches a rail mounted safety restraint device in the form of a carriage, which is roller mounted to the crown or ball of the rail, and to which carriage one end of a worker's fall arrest cable is attached. The carriage will move along the rail, pulled by the tether, as the worker moves along the rail, without unhooking and re-hooking the tether when changing work locations, yet will tend to stay in place, engaged on the rail, to secure the tether to the rail, in the event of a mis-hap such as the worker inadvertently falling off of a bridge. Such a device however is very heavy and a relatively complicated and expensive construction for an anchor, because of the roller system required.
Another device known to railway workers is a "bridgeman's ring" which loops about the crown of the rail and slides along it. The bridgeman's ring however must be attached at the end of a rail section, thus requiring the track to be unbolted for attachment of the ring to the rail if along an intermediate section of track.
Other patents of general background interest describing and illustrating safety anchors for use with beams are Olsen et al U.S. Pat. No. 5,156,233 issued Oct. 20, 1992 which describes and illustrates an anchor having a roller which slides in a track in a beam, for movement along the beam, and Smith U.S. Pat. No. 3,217,833 issued Nov. 16, 1965 which describes and illustrates an anchor in the form of a pair of interconnected jaws which releasably clamp to a beam, to co-operate with a safety bar, one end of which is secured to the anchor and the other end of which is secured to the belt of a worker.
It is an object of the present invention to provide a simple, lightweight anchor device which may be readily fastened to intermediate sections of rail as an anchor for a worker's fall arrest line. It is a further object of the present invention to provide such an anchor device which will be both secure when in anchoring position but which will be easily releasable for movement to a different location.